The death of a protester made some anti-globalisation groups decide not to join Saturday's demonstration, the final planned march against the G8 summit in Genoa.
Several British organisations, including Oxfam, Christian Aid and the Catholic Development Agency stayed away from the streets.
These organisations were part of a huge contingency of more than 700 groups comprising tens of thousands of demonstrators who descended on Genoa for the G8 summit meeting.
Protest organisers had called for a day of "direct action and civil disobedience", with attempts to cross into the red zone of exclusion which has sealed off the old port area where delegates and media are located.
Ahead of the demonstrations, several organisations pledged strong resistance to any attempt by police to stop their advance anywhere in the city.
Many of Saturday's clashes involved what has become known as the "black block".
It is believed this comprises several loosely organised anarchist and radical groups, wearing trademark black clothing, black hoods and gas masks.
One of the groups prominent during the violence was FAU, a German radical group with anarchist tendencies.
The Italian radical group Ya Basta! which declared war on the G8 summit before it had started, were also involved in violent clashes with police.
Many anti-globalisation organisations are concerned that violence takes the focus away from what they see as their real agenda.
The main protest organiser, Genoa Social Forum, sharply criticised the tactics of the "black block".
Some of the main groups protesting in Genoa were:
Genoa Social Forum Main organiser of Genoa protests and alternative forum
ATTAC! International pressure group for a more equal distribution of wealth
Drop the Debt London-based successor to Jubilee 2000, the international movement to cancel debts of the world's poorest countries
Ya Basta! Italian radical anti-globalisation group. Declared war on the G8
Globalise Resistance British-based socialist organisation, opposed to "the global growth of corporate power"
Indymedia Independent media organisation, writing and webcasting events from large demonstrations, by-passing what it sees as the corporate media
Tute Bianchi (White Overalls) Italian-based direct action group, using home-made equipment as defence against what it sees as police violence
FAU Freie ArbeiterInnen Union, German radical group with anarchist tendencies
In Genoa the protesters formed an alternative summit to the G8.
They hoped it would galvanise co-operation between hundreds of groups seeking alternatives to what they see as an undemocratic way of global rule represented by the G8.
One of the larger organisations present in Genoa is ATTAC. It seeks alternatives to what it sees as financial globalisation increasing social inequality.
Its spokesman, Christophe Agiton, told BBC News Online: "Genoa is important, because the world government [the G8] is here, making decisions important to everyone.
"We are here to show them people have other ideas about where the world needs to go.
"Protest is important, we need to show we are able to be wherever they are. Our existence is very serious, and we are not a narrow group."news.bbc.co.uk/hi/english/world/europe/newsid_1450000/1450323.stmE-mail this article